On Two Problems in the Multivariate Approximation
نویسنده
چکیده
The paper contains two theorems on approximation of functions with bounbed mixed derivative. These theorems give some progress in two old open problems. The first one gives, in particular, an upper estimate in the Bernstein L1-inequality for trigonometric polynomials on two variables with harmonics in hyperbolic crosses. The second one gives the order of the entropy numbers and Kolmogorov’s widths in the L∞-norm of the class MW r ∞,α of functions of two variables.
منابع مشابه
Verification of an Evolutionary-based Wavelet Neural Network Model for Nonlinear Function Approximation
Nonlinear function approximation is one of the most important tasks in system analysis and identification. Several models have been presented to achieve an accurate approximation on nonlinear mathematics functions. However, the majority of the models are specific to certain problems and systems. In this paper, an evolutionary-based wavelet neural network model is proposed for structure definiti...
متن کاملUniversal Approximation of Interval-valued Fuzzy Systems Based on Interval-valued Implications
It is firstly proved that the multi-input-single-output (MISO) fuzzy systems based on interval-valued $R$- and $S$-implications can approximate any continuous function defined on a compact set to arbitrary accuracy. A formula to compute the lower upper bounds on the number of interval-valued fuzzy sets needed to achieve a pre-specified approximation accuracy for an arbitrary multivariate con...
متن کاملOptimal Pareto Parametric Analysis of Two Dimensional Steady-State Heat Conduction Problems by MLPG Method
Numerical solutions obtained by the Meshless Local Petrov-Galerkin (MLPG) method are presented for two dimensional steady-state heat conduction problems. The MLPG method is a truly meshless approach, and neither the nodal connectivity nor the background mesh is required for solving the initial-boundary-value problem. The penalty method is adopted to efficiently enforce the essential boundary co...
متن کاملAn ${cal O}(h^{8})$ optimal B-spline collocation for solving higher order boundary value problems
As we know the approximation solution of seventh order two points boundary value problems based on B-spline of degree eight has only ${cal O}(h^{2})$ accuracy and this approximation is non-optimal. In this work, we obtain an optimal spline collocation method for solving the general nonlinear seventh order two points boundary value problems. The ${cal O}(h^{8})$ convergence analysis, mainly base...
متن کاملStudy on multi-objective nonlinear programming in optimization of the rough interval constraints
This paper deals with multi- objective nonlinear programming problem having rough intervals in the constraints. The problem is approached by taking maximum value range and minimum value range inequalities as constraints conditions, reduces it into two classical multi-objective nonlinear programming problems, called lower and upper approximation problems. All of the lower and upper approximatio...
متن کاملMinimizing a General Penalty Function on a Single Machine via Developing Approximation Algorithms and FPTASs
This paper addresses the Tardy/Lost penalty minimization on a single machine. According to this penalty criterion, if the tardiness of a job exceeds a predefined value, the job will be lost and penalized by a fixed value. Besides its application in real world problems, Tardy/Lost measure is a general form for popular objective functions like weighted tardiness, late work and tardiness with reje...
متن کامل